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Tankless Water Heater vs. Eternal Hybrid Water Heater
Comparing Eternal Hybrid Water Heater to Tankless Water Heater reveals the differences.
By: Al Johnson
Tankless water heaters are becoming more popular, partly because of the 30% federal tax credit. There are more and more manufactures entering the market with different models. The major manufactures are Noritz, Rinnai, Bosch, Takagi, Navien, Quietside and Eternal Hybrid.
Let’s take quick look at the working of tankless water heater first. Generally Gas powered (Natural or Liquid Propane Gas) are the only type that can provide enough hot water, electric models require a lot of power and are not economical.
In simple terms the water is forced through a spiral of pipes (heat exchanger) and as the water flows through the pipes a gas heater heats the pipes. The heat is then transferred to heating the water. Unlike traditional water heater there is no tank holding and keeping water hot.
As with everything there are pros and cons. Let’s see the Pros first.
Endless hot water since there is no tank to run of hot water. That is important if you want to take a bath and have hot water left over.
Saves Energy, Very efficient and staying efficient. Some Tankless Water Heaters are now up to amazingly 98% efficient, meaning that only 2% of the energy is wasted and not used for heating the water. Traditional tankless water heaters are 30% to 50% to start with when new and decrease rapidly over time because of sediment and other build up in the tank.
Clean hot water. That is important if you use hot water for cooking or other uses besides showering. Water in the tank water heater is prone to bacteria growth, rust and sediments that are unhealthy.
High Capacity. If sized right multiple people can take showers at the same time and not to worry about cold showers, very important if you get to take shower after everyone else, especially if you have teenagers at home.
Here come the cons.
Higher initial Cost is mainly due to higher installation cost although with some newer condensing models the installation is becoming easier and less costly.
Need Electricity to run. Electricity is used to control the heating process, not the heating. The computer that controls the valves and the heating can be run on a backup battery system if desired at additional cost. This is usually not a con.
Minimum flow rate needed. Tankless Water Heaters need a minimum flow to operate, usually 05. Gallon per minute (GPM). That is you cannot have the faucets just trickling hot water when brushing or shaving, a bad idea anyway, wastes too much water.
Now finally what is with the Eternal Hybrid Water Heater?
The Eternal has a unique way of heating the water. It has a 2 gallon tank where the water is kept hot inside. So instead of having a 40 gallon tank like your regular water the eternal has a 2 gallon tank.
This allows overcoming the con of a tankless water heater where you cannot “trickle” hot water. Now the water is drawn from the small tank and the unit keeps replenishing that, without going to great technical details of it. Eternal works like a tankless water heater with a built-in 2 gallon tank.
Is it a good idea? Well, it depends if you are willing to pay the higher price for the convenience of being able to “trickle” hot water and roughly 4% more efficiency.
The heat loss through the 2 gallon tank is very small and need not to be considered but there is a small chance of sediment buildup again because of the small tank.
Overall it is a good idea but not a must have in most instances.
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Just Tankless is specialized in Tankless Water Heating for domestic water and hydronic floor heating and other boiler applications for residential, commercial and industrial. Just Tankless is certified by all major manufactures.
Page Updated Last on: Apr 20, 2011